Tunnel-driving machine.



No. 891,473. PATENIBD JUNI: 23, 1908.

G. A. IOWLBR. 'TUNNEL DRIVING MACHINE.

APPLICATION IILD JULY 30, 1907.

s SHEETS-SHEET '1.

WNY...

I' TNSSE`S: M

A TTORNE Y No. 891,473. PATBNTED JUNE z3, 190s.

G. A. POWLER. y I

TUNNEL DRIVING MACHINE.

APPLICATION FILED lJULY 30, 1907. I

4 WITNESSES: lNvENToR y ATTORNEY 6 SHEETS-,SHEET 2.

No. 891,473. PATBNTEDJUNE 23. 1908. G. A. POWLER.

TUNNEL DRIVING MACHINE.

APPLICATION FILED JULY 30. 1907.

6 SHEETS-SHEET 4.

WITNESSES: IN VEN TOR ATTORNEY G, A. POWER, TUNNELDRIVINGAMAGHINE,

, APPIIQATIQN n nn JULY so 1907 s SEEETSAHEM 5 WITNESSES:

INVENTQR G. A. TOWLER.Y T'UNNEL'DRIVING MACHINE, APPLICATION PIL-BD JULY 30,1907'..

PATENTED JUNE 23, 1908.

6SHEETS-SHEET 6.

WITNESSES:

IN VEN TUR I Be it known inirrnn sfra'rns Parana* onnion.

GEORGE ALLENiFOWLER', OF )GEORGETOl/VN, COLORADO, ASSIGNDR OF ONE-HALF TO EDWARD I. WILCOX, OF DENVER, COLORADO, AND ONE-FOURTH TO FRANK V. GOETZ, OF CLEAR CREEK COUNTY, COLORADO.

TUNNEL-DRIVING MACHINE .v

No. 891,473.y

4Patented :rune 2e, 1908'.

Application inea Jiiiy 3o, 1907. seriai No. esame.

l To all whom it may concern:

FOWLER, a citizen of the United States, re-

Y siding at Georgetown, in the county of Clear Creek and State of Colorado, have invented a newv and useful Tunnel Driving or Cutting Machine, of which the .following a speciiication.

My invention is directed tothe production of a pneumatic-mining machine, having a plurality of thrust actuated drills adapted particularly for tunneling o r driving operations and in which the drills are carried by a pivotally mounted block which, in its -cuttin operation, is automatically caused totrave back and forth reducing the wall of the breast in' the arc of a circle for giving a clearance at the sides of the machine; and in which the extent of such travel is automatically determined, and in connection with the arrangement of the drills at the top and at the bottom of the block and the oscillation of the block provide thereby a clearance for the advance of the car at its sides, at its top i and at its bottom in cutting its Way in forming the tunnel.

- Thrusting drills disposed in the block andV caused to be actuated in groups which alternate in striking `a thrusting blow, is a feature of my invention. For mounting .this drill block a car isvprovided with means wherebyA it is advanced and held' during the driving operations of the drills, and in the claims appended hereto I will'set out the parts and combinations of parts wherein my invention resides in connection with the accompanying drawings in which l Figure 1 represents in side elevation a rock tunneling or drii-inginachine cnibodying'my invention and in which a swing drill-block having a multiple of drills, isinounted upon wheelsa'nd the drills are adapted to be ae: tuatedv by pneumatic power thrusting hammers, and iiieans'whereby the d'rillfblock is' caused to be turned to the right or to the left as it is moved forward 'against the breast. Fig. Ziis a top view of so milch of the machine as shows the mechanism by which the swing drill-block is automatically turned to the right o r to the left in its relation to the breast being tunneled. F ig. 3 is an enlarged detail view of the adjustable connection of the 'guide-arms by which. the machine is held and guided againsttlie side walls of the tunnel.

that I, GEORGE ALLEN Fig. 8, the drill-chucks and their hammers.

being removed to expose their receiving chambers, the upper half art of said block part of theL being shown in 4side e evation running .A through the interior air passa e 88 of Fig. 8. ,l 2"; I Fig. 7 is an enlarged horizonteJ section taken 1 `on the line A-B of Figs. 4 and 6 showing hammers in elevation and the relation of the side ,hammers and the drill chuck-heads to the air ports vand passages by which the hammers are actuated. Fig. 8 is ahorizontal section taken on the line C7-Dof Figs. 4 and 6, but showing the side hammers in elevation and their relation to someof the ports-and passages the reverse of that shown in Fig. 7. Fig. 9r is a top view on smaller i scale .of the muck-pan for the cuttings or chippings and its relation to the conveyer for conveying the chippings awty. Fig. tl11g er sca. e

shows in side elevation on sina inuckan'as it is suspended from the swing drill-b o ck and a portion of the conveyer .in vertical section.

ceives the muck from the conveyer and its operating gear. Fig. 12 is an enlarged detail showing in side view the relation of the elevator to the conveyer and the gear by which they are operated. Fig. 13 shows an -enlarged detail top view of the gear connection with the shaft of the rear su portingk wheels for the purpose of manually ceding themachine up to the breast of the tunnel and to lock it in such position when at work. Fig. ,14 is an enlarged side view of the parts shown in Fig. 13. Fig. 15 is an enlarged top view in detail of that part of the gear mechanism drill swing block. Fig 17 is an enlarged side View of the detail parts shown in Fig.`16..

Fig. .18 shows enlarged front and side views Fig. 1,1 is an'enlar ed de-` tail top view of the bucket elevator t at ref whereby the swing drill-block is caused to of the drill-bit and its guide bearing collar .in the facelate fixed to the Yfront of the swing drilllock; Fig. 19 is an enlarged vertical sectional view oi the air compresser showing its valved ports and piston-rod` operating connections and connection 'for supplying compressed air thereto tothe cempresser, and the provision whereby the com- Vpressed air is caused te effect the reciproca-y tion et .the drills. 54,- Herein I have used the terms major and minor channels in the drill-block, the maior vdriven axle 8, journaled in bearings and carrying traction Wheels 2, Which, in connection with Wheels 40 journaled in bearings at the` forward end of the car, form a rolling support for the car.

vAn air compressor 59, is carried by the 'car and consists of a cylinder' 77, having a recipreoatory piston 132 therein, its piston-red 73, being connected by apitman, te a crank 131, the shalt of Which-carries at its outer end a belt-pulley 5 7 te which power for reciprocating the piston 132 is applied..

An air chamber 133, formed on the eXterier of the cylinder, communicates with the interior thereof by ports lecateden each side of the piston, the upper port being controlled by a valve 74 andthe lower port by a valve 75, the valves opening inwardly into the cylinder against the force et their springs. The air chamber 133 is in communication by means of a pipe 76, with a eonn'iressed air supply which maintains a practically unvarying pressure in the chamber 133. (ipposite this chamber the cylilnler is provided withopenings, one at each side of the piston. the upper openingr haring a hose or pipe ell connected therewith, and the lower opening a hose or pipe 53, both connecting- With the drill-block. ln this description of the source. and use of' the compressed air as the power for operating the drills, it wiltbe understood that the pipe 7 6, leads to the source ol such power and that from this source the air is received and delivered ironia compressing and expanding machine 59, the function of vtl'iich is te compress and distribute the air therefrom inte the chambers of the drill-bleek and Which Will hereinafter be designated the air compressor and distributer.

Upper and lower horizontal brackets 50 and 2S respectively are rigidly secured to and project from the front end ol" the car. 'These raekets pivotally'suppert a drill-block 33, having an upper bearing 49, Fig. 1, which rests upon the ear bracket 50, and is pivolied thereto by a stud 51, said block having also a ameter than the front portieri, all of the lchambers in a section being preferably in lower bearing 30,' superimposed. ,upon a segmental Worin Wheel 26 rigidly secured to the drill-blr'iek and resting upon the car bracket 2S. A pivot pin 55, in vertical alinement i with the pivot pin 51, depends from the bracket 30, and passes throughthe center of Worin segment 26,'an d the lower bearing 2S.

rl`he drillsbleck 33, is formed preferably of three vertical sections 146, 1117 and 14S, which are iirmly connected together side by side. A

Each. section is provided with a plurality et cylindrical drill-chambers all ei which, excepting the u permost and lewermost ones, are hoizonta 'ly disposed, the excepted ones 30 being inclined outwardly to the face of the block ter aipurpose hereinafter stated.

Each chamber is composed of a front portien 139 and a rear portieri 13a, of lesser divertical alinement therein; the chambers in the outer sections being in horizontal alinement, and each chamber in the middle sectien beingbelow the horizontal plane connecting a chamber-in one et the outer sections Whieh'is in horizontal alinement with a chamber in the other outer section. A drill carrying chuck 38, and its actuating hammer or piston 84, are 'seated in each chamber, the chuck having a head adapted t'o be reciprocated in the front portion 139, the shank ol the chuck Werking through an opening in a screwthreaded plug 78 which closes the liront en d of' the chamber, and the hammer being 100 adapted to be reciprocated inv the portion 134,'the forward .movement of the hammer resulting in the thrusting bleuvv ol its drill. The drill-block is provided with major vertical ehannels 86 and, and minor vertical 105 channels 79, and S1. The major and minor channels extend continuously throughmit a suilicient portion of the length of the drillblock to accommodate all of the chambers therein, these channels beingT inelosed by the drill-block except at the outlets hereinafter indicated. 1 i

The minor 'channel 79 cmineeted to the major channel 3G by a horizontal passage 145 shownin dotted lines in Figs. 7 and 8; and 115 channel Iis connected to channel 8S by a horizontal channel similar to channel 145, and shown in dotted lines in Figs, 7 and S, and in full lines in Fig. 6. The channels Sli and 8a communicate respectively with the 120 exterior of the `block by horizontal openings 60 and 53', the former being connected te the hose or pipe 60, and the latter to the hose or pipe 58 leading from the cylinder et'v the compressor. The drills are actuated in 125 groups which alternate in striking a blow, and for this reason three drills constitute a transverse group, composed of a drill in one ot' the outer sections, the alining drill in the other outer section, and the drill in the inidvstriking a blow, under the impulse of the forward movement of their actuating hammers,

while the se'ond, fourth, sixth, etc., groups of actuating hammers are moving backward to their initial position. Thus one vhalf of the number of drills of the block are struck by their hammers to drive them into contact connected to the major channels 86 and- 88,

with the wall, at the same time that the other half of the number of hammers are returning to their initial position.' To accomplish this result, the successive transverse groups are in a mannerl to be now indicated.

Referring toFigs. 7 and 8, which are taken ondifierent horizontal planes, the plane of Fig. 7, being above that of Fig.,8, and' each figure' therefore representing successive transverse roups of hammers and chucks, the middle ammer and chuck of each group being shown in dotted-lines, it will beseen that each drill-chamber is connected at its back end, at the rear of the piston, to a major vertical channel; that it isconnected atits front end in front of the chuck-head by means of a transverse passage, aminor vertical channel, and a horizontal channel, to the same i major channel; and that said chamber is connected at a point at the rear of the chuck-head and in front of the hammer to the other major channel. Therefore, when air is compressed in the first mentioned major channel-it drives the hammer forward .against the chuck-head, and simultaneously compressed air'is admitted infront of the Achuck-head to cushion the'blow of the ham- -mer, and as air in the second mentioned major channel was simultaneously expanded,

pressure was reduced between the rear face i of the chuck-head and the front face of the hammer thus permitting the ressurc at the It will rear of the hammer to prepon erate. be noted that these'stated connections of chambers to the major channels 86 and 88 as shown, in Fig. 8, are the reverse in their connections with the same major channels to that shown in Fig.l 7; and these connections lthus alternate inv regard to the. successive transverse grou s which are arranged vertically in ,the drill-block. Referring' now to the passages shown in Fig. l7 85 indicates the passage which extends from-the back end of A theouter chambers at the rear of the hamsl mer, tothemajor channel 88, connecting with that channel through port 87, and 119 rencsents in dotted lines, theequivalent port w ich 'connects the middle chamber of this group to major channel 88. As before stated channel 88 is connected to channel 81-.by

vthe next 'like part of the middle chamber.

' and in full lines in'Fig. 6.

means of a transverse passage 83, and a pas-- sage 135 extending from passage83to channel 86. The equivalent connection for the middle chamber is shown in dotted linesat c Referring now to Fig. 8, `which represents Aower transverse group to `that shown in Fi 7, the passage 94, connecting with channe 86, through port 95, leads to the rear ends ofthe outer chambers; and a passage 141, shown in dotted lines, leads to a c The front ends of the two outer of these three chambers are connected to the same channel 86, by means ofa transverse passage 92 which connects with channel .7 9, a like portion of the middle chamber being connected to this channel-79 by a passage 138,' shown in dotted lines, in this figure. Channel 79 is as before stated `connected with'channel 86, by the horizontal channel 145. The outer chambers intermediate the rear of their chucklheads and the front of` their hammers, are

connected with the other channel 88, by assages 93 and 136, the former exten( ing transversely between the outer chambers, andthe latter passa e connectin passage 98 to channel 88. A li re portion of the middle chamber is connected `,to channel 88, by a passage A105 shown in dotted lines in Fig. 8,

- The operation of the drills and their actuating means are as follows: The pipe 76, which leads `from any suitable compressed air supjv ply, maintains a constant and practically uniform air .pressure at formstancc 100v pounds pressure in the chamber 133 of the air compressor, and, when the'piston 132 is not in'operationfthis air, ata pressure. of 100` pounds, enters, through the ports controlled by valves 74 and 75, and fills each end of the cylinder 77; from the opposite ends of which it flows through the pipes 60 and. 58 to the maj or channels 86 and 88 respectively of the drill-block; andas all the'chambers therein vare connected, with the channels 86 and 88,

at three points, in front of the chuck-head, between the chuck-head and hammer, and at the rear .of hammer, it is evident that both faces of the chuck-heads rand both faces of the hammers will be under pressure of 100 pounds, hence will be in a state of e uilibrium; and at this point it may be wel to say that to operate the drills, the compressed air is not ex austed to the atmosphere but the pressure of this compressed air, by means of the operation of the piston 132, as hereinafter explained is increased in one part of a supply of compressed air, hence compressingchannel 86.

moving backward to their initial position,-

and the group of hammers,-shown in Fig. 8, the group next belowthat shown in Fig. 7', are at the lsame time advancing forward to strike their chucks the arrows on the ham mers indicating their direction of movement;

and the arrows in the chambers and passages representing the expansion and compression of the airl therein, expanding air being represented as leaving a chamber, and air 'compressed being represented as entering a chamber. This movement ofthe hammers in Figs. 7 and 8, is accomplished in the following manner: The piston 132 of the air compressor moving upwardly in i-ts cylinder, compresses the volume of air in the upper end of the cylinder, the valve 7 4 closing to prevent air being forced back to the point of also the air in the hose 60 connected therewith and also inchannel 8.6 connecting with hose G0 and in the passages connected with 'Simultaneously the air in the lower Vend of the cylinder 5.7, in hose 58, in channel 88, and in the passages connected therewith expanded. equal air pressures in channels 86 and S8, and in the passages connected with each, the pressure in channel S6 and its connecting passages being greater than that in channel S8 and its connectingpassages; and it is ythese unequal air pressures that cause the operation of drills. Referring again to Fig. 7, it will be seen that the volumeof air in thc chambers, now under greater pressure lies between the rear of the chuckheads and the front of the hammers, this portion of the chambers being ,in communication with the channel S6, now under greater pressure, by passages 135 and 83 which lead to the two outer chambers, and by passage 137 .which leads to the middle chamber. The volumes of air in the same chambers at the same time as the foregoing which are under lesser pressure, lie between the rea-r of their chambers and 'also between the vfront ofthe chuckheads and therear of the closing plugs 7S., the first indicated portion of the chambers being in communication with the channel SS,

now under lesser pressure, by passages and 119 the former leading from the rear of the two outer chambers, and the latter from the rear of the middle chamber, and the second indicated portion of the chambers being in communication with chan-nel 88, by

means of passages 82 and 103 which lead from the frontA of the chuck-heads to lminor channel 81, the passage S2, leading from the two outer chambers and the passage 103 from the middle chamber; and channel 81 is connected to channel 8S by channel 125.

This results in un.

Thus the hammers shown in Fig. 7, have a greater pressure on their front faces than on their rear faceshen`ce are driven backward 'by this inequality of pressure. At the vvsame time that the foregoing movementvof the transverse group of hammers and chucks shown in Fig'. 7 was taking place, the transverse group next below, and shown in Fig. 8,

were operating as follows: The air of greater pressure, in channel 86, and passage 94 and 1 411 (the latter leading to the iniddlefchamber) connected therewith, and vth the chambers at the-rear of the hammers, exerted its force against the rear of the hammers; and this greater pressure of channel S6 was at the same time exerted against the front of the chuck-heads by means of assages 92 and 13S (the latter lea-ding to tie middle chamber) which lead therefrom to minor channel 79v the latter being .connected to channel- 86 by -channel 145; and the lesser pressure Vvof channel 8S was commiuiicated to the front faces the hammers and the rear faces of the chuck-heads by means of passage 93 and its connection 136 'and the passage 105 of the mid dleehaniber. Thus the hammers shown in Fig. 8 having greater pressure at their rear faces than at their front faces are'driven forward to strike their chucks; and as the air pressure on the front face of each chuck is greater than that en its rear face, the blow of the hammer against itsc'hu'ck is cushioned to save the block lparts from'injury. lf the movement of the air compressor piston be now considered as reversed, that is, that it is now moving downwardly in its cylinder, the pressure throughout the system will be reversed; air will be compressed in the lower end of the cylinder, in hose 5S, in major channels 8S, in horizontalchannel 125, in minor channel 81, passages 85, 82 and 103 (Fig. 7) and in passages 105 andi93 and 136 (Fig. S) and air will expand in the upper end of cylinder, in hose 60, in major channel S6, in horizontalchannel 145, in minor channel 7S), in passages 83, 135 and 137 (Fig. 7) and passages Het, 92 and 138 (Fig. 8). Under this condition of pressure the hammers of Fig. 7

will move forward against their chucks..

which are simultaneously cushioned, and

the hammers of Fig. 8, will move backward to their initial position. Thus it will be seen that one movement of the pistonl32 causes. ene transverse group ofhammers to strike a blow which is cushioned and at the saine time causes' the f next vertical transverse connect with the continuous vertical 'minor 4channels 79 and 81 and major channels 86 vand 88, are repeated vertically in the block, it will be understood that the successive trans# verse groups operate in the same manner as explained in detail in connection withthese groups; thus for example, while the iirst, third, fifth, etc., transverse groups of drills are striking a thrusting blow under the i1npulse of the forward movement of their hammers, the second, fourth, sixth, etc., trans verse groups of hammers are moving rearA wardly to their initial position, and vice versa.

The air cushion formed in front of the chuck-head protect the block parts from in jury should the' drill notstrike the wall.

This air cushion does not reduce the desired force ofthe blow of its hammer as the area of the front face of the chuck, the face sub- -jected to cushioning pressure, is less than the area of the face of the hammer subjected to the same air pressure, this difference .of area being due to the fact that the transverse area of the shank of the chuck is no t subjected to ressure; and the momentum which the ammer acquires aids in the force of its blow.

' The drill-block is formed in three sections in order that `the channels, passages and ports, may be readily formed therein. In ractice the volume' of the compression cyhnder is equal to the combined volumes of all the chambers in the drill-block. Thus it will be i seen that the chambers .of the drill-block, and

and drills are thus operated.

the passages leading to the chambers, are constantly supplied through the pipe 7 6, with air under pressure; and it will also be seen that this supplied pressure maintains the hammers and drill-chucks in equilibrium, hence motionless except when the iston 132 of air compressor 59 is actuated. i

plied pressure in` one part of a chamber, reduces the lsupplied pressure in other parts of the same chamber hence destroys the equi'' libriumexisting therein, and the hammers lt will also be seen that the air under pressure supplied through pipe 76 is never exhausted to the atmosphere but is acted upon by the piston 132 as hereinbefore explained.

The drill-block on its side faces near the bottom thereof, are formed with brackets 32 each of which adjustably carries and retains a s-hde-plate 31, which carries a wheell 29 disposed to'travel 1n areas of which the pivotal point of the drill-block is the center and adapted also to contact'with the ground and to thus sustain the-drill-block and su )port llates upon its pivotal support. These wheels re-v lieve the brackets '28 and 50 of theggreater part of the weight of the drill-block, hence reducing to a minimum the friction on the bearings due to the oscillation of the drillhen piston 132 is actuated it increases the supblock'. The plates 31 are adjusted by means of screws 52 which are swiveled to the slide plates and engage threads in the brackets 32.

Secured to the front ofthe drill-block by brackets 37, is a combined guide and shield composed of a back-plate 36 and forwardly projecting side-plates 34 which protect the machine fromthe cuttings. The plate 36 is provided with openings having their centers -in alinement with the chambers of`theA drill-v -block, and at each opening the plate has a drillguide 121 which is provided withiintersecting rectangular openings which are adapted to receive the ribs of drills 35 to guide and support the drills and keep them in alinement with the axis of their chambers during their reci rocation.,

, Each r rill is secured to its chuck 38, (see Fig. 5) by means of the ribs of the former en tering corresponding slots 101 in the shank of the latter and being retained therein by a heavy spring ring 100, provided with an in- 98in the chuckVand ent-ers' also a registering slot in the rib of the drill intersecting the slot 98. This occurs when the ring V100 is in place embracing the shank of the chuck. As the resilienc of the spring-ring 100 is suflicient to hol it in position around the shank ofthe chuck, the rib of the spring will firmly holdthe drill in engagement with the chuck.

The ldrill-block is rovided at its center `wardly projecting rib 99 which enters a slot and below the line o drill-chambers with'a circular, horizontally disposed chamber 142, (Fig. 6) the frontend of which communicates by a passage 143 with one of the major channels, the rear end communicating by a passage 112 with theother major channel. The chamber 142 receives a piston 117 whose rod 115 asses through anl opening in the plug Whicli closes the front end of the chamber 142. It will be-seen therefore that thexpiston 117 is actuated by the air pressure in the same manner as the hammers, The pistonrod 115 is provided with a vertical hole through which loosely passes a stud 116 projecting from vthe front end of a reciprocating muck-pan 54. vertically in the hole in the piston-rod thus letting the front end of the pan rest on the ionA This stud is free to slide s ground, while at about the middle of its length' the pan is pivotally hung to the drillblock by arms '53, one arm at each side of the block so that the weight of the front end will preponderatc. The bottom` of the muckpan is also provided with upwardly and rearwardly inclining ribs 144, the purpose of which is to hold and prevent the return of the muck by the movement of the pan. The

piston-rod has fastened to it, a collai` 113, and a bumper-spring 114, on said rod. The rear end of the muck-pan enters the front end .of an apron 56 which houses a slot conveyer 71 actuated by sprocket-gears 70, the shaftof one gear 7 0 carrying a spur gear 70 which meshes with a gear 5, the shaft of vvhch`car-y lower shaft of this bucket'conveyer is supported by brackets 4 and 7 which also support the rear end of the apron 56, which at this end terminates in the boot 68, ofthe bucket-conveyer. ri'he shaft 66, is driven from the shaft 62, by the belt 61', and shaft 66, in turn drives shaft 141 which carries the lower roller 140 of conveyor 67, and also carries the spurgear 5, which meshes with gear and drives it. Shaft l62 is connected to a motor element 19 by a belt 63, and motor 19 is connected to, and actuates the belt-pulleyv 57 of the air compressor. Counter-shaft 62 is also connected by belt 144 to a pulley 1S, th inner end of the shaft of-which has rigidly secured thereto a bevel gear 124, which is in constant engage-ment with a bevel-gear 17 carried by a shaftv 21 journaled upon the car and extending longitudinally thereof. The shaft 21 has a bevel-gear 14 fixed thereto at its rear end, anda bevel-gear 22, fixed to its front end. The bevel gear 22 is adapted to mesh with either one of two bevel-gears 23 and 24 both carried by a shaft 13 journaled as Shown, and uponwliich they arc fra-c to slide, but 'with whicli they are caused to rotate by thel medium of the ordinary feather and groove arrangement. The shaft 13 has rigidly secured thereto, intermediate the gears 23 and 24, a worm 25, which is in mesh with the segmental. worin-wheel 26 fixed to the drill-block 33. Each of the'bevel-gearsz and 24 is formed. with an annular groove, into which project pins 129, fired to a rod 127, slidablT supported by brackets 126 upon the bearings of the shaft 13. The slide rod 127 carries an upwardly projecting pin 128 which is adapted to bestruck by either oftwo arms 27 or 39 carried by the segmental worin-wheel 26 which, in Fig. 15 forthe purpose of illustrating the arms 27 and 39 in this view, is shown broken. A

rl`he bevel-gear 14 carried by the shaft 21 at its rear end, is adapted to mesh with either of two bevel-gears 10 or 11 rigidly secured to a sleeve 9 carried by the shaft S, which. forms the rear axle of the car, and upon which it is free to slide but is compelled to rotateherewith by the usual clutch feather and groove arrangement. The sleeve groove is adapted to be engaged and operated by the usual clutch lever (not shown) and by means of which either of gears 10 or 11 can be shifted into engagement with bevel-gear 14 in the manner of a clutch. The rear axle 8,' has also secured thereto a worin-wheel Y12 which is engaged by a worin 15 mounted in a bracket 16 which is' ada1 ted to be secured to the frame of car by boils 142 (see Fig. 14).

The worm is provided at its upper end with a removable socket adapted to` receive the square end of a key provided at its upper end with a hand wheel 130, Vto be usedffor a purpose hereinafter stated.

Carried at each side of the car, are means A for guiding the car straight in its movements in the tunnel and for holding the car inta-nyposition therein, and it consists of a pair of arms 41-41 at each side of the car, arranged with'their abutting ends pivotedthereto'by,

means of a bracket about mediately of the length of the car and extending from their pivotal connection 44, obliquely outward toward the front and toward the rear and terminating iii a roller 42, adapted to roll,

upon the vertical wall as the car advances and beingrbraced to the car their relative positions causes them` to have the function of a straight edge in keeping the carin a straight line. For this purpose 4means are provided for maintaining these arms in rigid relation asI and allow of their ad'ustinent to hold the rolls nearer to or fuit er from the car and the means shown for this purpose consists of a screw-rod 4S, pivoted to each arm near its roller end and is connected to the car framel by a swivel joint formed by a bracket 45,

secured to the car and ascrew-sleeve 7.2,

mounted. by a bearing 46,- secured in the bracket as in Fig.' 3. on the rod abuts against the end of the screwsleeve and the adjustment of the pivoted arms made byl setting the rods further into or out of the screw-sleeve by means of the mit and when so set the nut serves to lock the screw-rod.

Each of the pivoted arms is provided near its outer end with a plurality of holes into anyone of which a pin 43 serves to connect the screw-rod to the arm, the end of which for that plurposebeing forked to ein# brace the arm. t will be understood that the swivel-screw-sleeve joint while allowing the adjustment of the screw-rod, the adjust-v able connection of the rod with the arm isthc arm. j

The operation of my invention, in tunneling not now including a detailedstatement ofthe operation of the drills and their actuating means as these vhave been'heretofore eX- pl ai'ncd, is as follows: The worm 15, having been removed after loosening its bolts 142, to unlock the traction shaft, the machine is broughtfinto position in; a tunnel with its drills in operative relation to a breast-wall. This can 'lie accomplishedby power transmitted fr0 nthe motor 19, to thel counter shaft 62, 'which in turn actua-tes the pulley 18 and its gear 124, the latter through the medium of bevel-gear 17 actuating the bevel-gear 14, and the sleeve?) having been shifted to bring bevel-'gear 11 into contact with gear 14. YWhen this-is done the shaft S or the rear axle of the machine is revolved provided to suit the adjustment in or out of An adjusting-nut 47' its former movement.

fthe nuts 47. .If it is desired to advance the machine to this position, by the a plication of manual power, the worm 15 is le t in place on the car, and the sleeve 9 shifted to keep its bevel gears 1() and 11 out Aof engagement with the bevel-gear 1 4. By then turning the Ahand-wheel 13() the worm-wheel will be rotated, turning the rear axle and the wheels thereon and the car is thereby advanced to the desired position, and the worm by locking the worm-wheel will prevent the rear axlefrom turning and thus kee the -car from moving by the thrusting action of the drills, out of the desired position. Gener-A ally, the gear-wheels 10 and 11 and theircooperating means are used when it is --desired to move the machine aconsiderable distance, the worm-gearing 12y and 15 being used at other times...

With the drills in operative relation to the breast-wall, the air compressor is actuated and, as before explained the drills 35 are reciprocated intqand out of contact with `the breast wall. is the drills are reciprocating, the shaft 21 is also being turned by its rear end bevelfgear 17 which is in mesh with bevel-pinion 124, and the gear 22 carried by shaft 21 engages with which either one of the gears 23 or 24 that is shiftedinto mesh with it, the gear 23, for instance, as shown in Fig. 2. The consequent actuation of the gear 23, causes the rotation of the worm 25 which in turn moves the segmental worm-wheel 26, this resulting in turning the drill-block about its pivotal axis and cutting the breast in the arc of a circle. As the drill-block. continues to turn, its arm 27, comes in contact with the pin 128 of slide-bar 127, pushing the slide-bar towards the gear 23, and by means of the pin enga-gement` 129 of the slide-bar with these gears, the gear 23 is pushed out of engagement with the gear 22 and the bevel-gear 24 is forced into engagement therewith. The rotation of the gear 24 now changes the di-- rection of rotation of the worm 25 hence of the segmental worm 26 and the drilleblock is now turned in a direction opposite to that of the impulse of gear'24 continues, the pin 39 comes in contact with the pin 123an lthe gears 23 .and 24 are again shifted. This reversal of direction of movement ofthe' drillblock by these means, is tlu-reafter repeated. The cuttings from the drills. the water used against the breastwall and the nmterial As movement under loosened thereby, fall to the round and arel causing a j ar and sudden stoppage of the pan which throwsv thematerial 1t carries rearward upon the corrugated bottom of the muck-pan, and, finally, by reason of the con? tinued reciprocations and jars of the muckpan the material thereon isthrown from its rear end upon the bottom of apron 56, where it is caught by the slot conveyor 71 and earried farther to the rear and delivered into' the boot of the'bucket conveyer 67 which in turn elevates and dumps it into a car or tank, not shown, for removal from the tunnel. l As the drill-block swings from one side to the other, the muckfpan, being Ycarried by it, conseuently swings with it but the rear end of t e pan always maintains a proper working relation to the slot conveyer 2l and its apronV 56 as is'illustrated in Fig. 9. ,t

If it is desired to move the carbackward by mechanical power, the opposite gear 10 for illustration, from that usedto 'move the car forward, is thrown into engagement ywith the bevel-.Crear 14 and the arms 41 having been withdrawn from binding contact with the sides of the tunnel the car will then move rearward, it being assumedthat the worm 15 has been removed yfrom the car; or this worm, -if it be desired to move the car by the a plication of manu-al power can be used 'for t 'is 'purpose as will be'readily understood.

vAn advantageousfeature of my machine is its abilitypto cut a clearance for itself as it advancesin a tunnel, this it accomplishes laterally through the oscillation of the drillblock; and its vertical clearance, the excess of the vertical height of the cut over that of*A the machine, is secured by the upper and lower transverse rows of drills splaying or inclining outwardly as stated. Thus the cutting. ends of the top row of drills project above the top of the drill-block, and the cutting endsof the bottom rowof drills, in a like manner, project below the lower edge of the drill-block.

It is important to note that the pivotal mounting of the block is at its rear side, mediately of its width andmediately of the width of the car and in alinement with the shaft from which power for the oscillation of the block is delivered ,and that the extent of its oscillation enables the drills to cui' a snlli-` eiently wide area togive 'room for the ear and its connections to advance. l

5o far as I knowyand can find l am the .first to produce in an organized tunneling nmchine drills pneumatically operated in Groups that alternate in striking a thrusting bIoW by a process which consists in first subjecting the opposite faces of the drill actuators to equal pressures of compressed air, then simultaneously increasing the supplied ressure at one face of the actuators an decreasing the suppliedpressure at the other face of the actuators and then reversing the' unequal pressures on the faces of the drill actuators, the pressures on the corresponding faces ofthe drill actuators for one group beinfr the opposite of that for the`other Group.

I wish it to be understood that I onot desire to be limited to the exact details of-4 construction shown and described, for obvious modifications will occur to a person skilled in the art.

- I claim: L

1. In a tunnel driving machine, a car, a

block pivotally mounted upon thefcar so as to swing horizontally in front`thereof, thrusting drills carried. by the block," and means mounted on the car and on the block for automatically oscillating the drill-block,.

Aand adapted for continuous alternate contact-the means on'the block alternatingv With the means on the car for automatically oscillating the drill-block in both directions,

means for operating the drills, and means for causing the car to advance in thev cutting operation.

3. In a tunnel drivin@ machine, a car, a block pivotally mounted thereon, thrusting drillsl carried by saidv block, means for automatically oscillating the drill-block consisting of a slidable gear reversing device on the car, a segmental gear on the block, an yarm projecting diametrically from each side of the segmental gear, the arm on one side adapted to engage and shift the reversing gear device in one direction, the other of said arms adapted to engage and shift thereversin'g gear device in the opposite direction the engagements being incontinuous or alternate succession, means for continuously operating the segmental gear, means for opf erating the drills, and means for causing the car to advance in the cutting operation.

' 4. In a tunnel driving machine, the com-` bination with a car, of a drill-block pivotally 4mounted thereon, a worm segment fixed to the drill-block, a worm journaled upon the car and in mesh withthe worm se ment, a bevel-gear mounted upon :each en of the worin-shaft free to slide thereon but keyed to rotate therewith, a horizontal slidable bar continuously engaging both bevel-gears, a longitudinal shaft -journaled on the car, means for actuating this shaft, a bevel-gear fixed. to this shaft and adapted to actuate either of 'the bevel gears on the Worm-shaft, and arms extending from opposite sides of the segmental worm Wheel and adapted to automatically encrage and alternately contact with and move the slidable bar to. throw the gears on the worm-shaft into and out of engagement With the gear on the longitudinal shaft. A

5;. In a tunnel driving machine, the com-` bination with 'a car, of avdrill-block pivotally mounted thereon, a segmental worm wheel fixed to the rear of the drill-block, a Worm journaled on the car and in mesh with the segmental Worm-wheel, bevel-gears on the shaft of said worm; Wheel and at opposite sides thereof, the bevel-gears being `free to slide onthe worm-shaft but connected to rotate therewith, a longitudinal shaft journaled on the car,'me`ans for actuating this shaft, a bevel-gear ri idly secured to each end of the longitudina shaft, the frontgear being adapted to mesh with either one of the bevel-gears carried by the Worm-shaft, a slidable bar engaging the bevel-gears 23 and 24 means carried by the segmental worm and adapted to automatically engage said slidable bar to alternately throw the bevelgears on the worm shaft into enga ement with the front gear on the longitudina shaft, and means for continuously operatingr it, whereby to effect the continuous oscillation of the drill-block. d

6. In a tunnel driving machine, the combination with a car, of a drill-block pivotally supported by the car at itsfront, a segmental Worm fixed to the drill-block, a worm 25 j ournaled on the car, bevel gears carried by the shaft of the Worm one being at Deach side thereof the bevel gearskeyed to slide on the shaft, a longitudinal shaft journaled on the car, a bevel gear'fixed toits front end and adapted to 'engage either of the bevel-gears on the worin-shaft, a bevel-gear fixed' to the rearof the longitudinal shaft, means carried by the drill-block and adapted to alternately force the bevel-gears on the worm-'shaft into I block'pivotally mounted thereon, thrustingv dril'ls carried by the block, a pair of supporting Wheels one mounted at each end of the block in advance of its pivotal mounting, a

- connecting it to the pan for causing it to have a reci roeating movement.

8. n Aa tunnel driving machine, a ear, a block pivotally mounted thereon, thrusting drills carried by the block, a muck-pan suspended from-and beneath the block, a pair of supporting wheels one mounted at each end ofthe block in advance of its pivotal mounting, power driven gear mounted on the c ar, a gear fixed on the block both gears in constant engagement for causing the block to be continuously oseillated horizontally, and a com- Iressed air actuated piston carried by the lock'. and connected with the'pan for causing it to' have a reci irocatingmovement.

9. In a tunne driving machine, a car, a

-block pivotally mounted upon the car and projecting in front of it, supporting Wheels carried by the block, and adapted to travel in the are of a circle described by said block in front of the mounting pivots, drills carried by the block, a segmental worm fixed to the block, a Worm mounted upon the car and engaging the segmental Worm, and means for actuating said Worm to actuate the segmental worm and to cause the oscillation of the drill-block.

10. In a tunnel driving machine, a car, a block pivotally mountedupon the car andprojecting in front of it, Wheels adjustably supporting the block, thrusting drills carried by the block, a segmental worm fixed to the drill-block, a worm mounted upon the car and engaging the segmental worm, means carried by the car for actuating the Worm, means for reversing the direction of rotation of the -worm, a pan pivotally hung from the drill-block and adapted to take the material loosened by drilling, and means carried byy said block for reciprocating the pan.

11. In a tunnel driving machine and. in combination, a-car, a block pivotally mounted thereon, a pair ofsupporting Wheels one at each end of the block in advancel of its pivotal -mounting, thrusting drills carried by the block, power-driven mechanism mounted on `the car, a segmental gear fix-ed on the vblock in constant engagement with the car-gear whereby the block is caused to `be continuously oscillated, a muck-pan suspended from and beneath the block, means carried by the block for reciprocating the pan, an endless conveyer'mounted beneath the car, and an endless'conveyer mounted at the rear of the car both conveyors having geared connection, and means mounted on the car for actuating thc conveyors.

l2. .ln a tunnel driving machine, the comi thereon and projecting in vliront thereof the blor'kbcing provided with a plurality ol' drill clui-mbers. a drill-carrying chuck and its actuating liamnwr m cach chamber, -a pan fixed to the forward givomuy hung immane beneath thedriui lock, a piston mounted to reciprocate in a chamber in the lower portion of the drillblock, a nonnection extending from the rod of the piston to the pan and adapted to move the an in with the piston, an air compressorl carrled by the car and kfluid connections extending from the air compressor to the drillchambers and the piston-chamber and. adapted to convey the variations of air pressure in the chambers for the purpose stated. y

13. In a tunnel driving. machine, the combination with a' car, of a block pivotally mounted thereon and projecting in front thereof, the block being provided With a plurality of chambers and communicatin passages, `a thrusting vdrill in each cham `er, a pan ivotally suspended from and beneath the rill-block, a piston in a chamber at the powerportion of the ydrill-block, said blockaving openings 58-60 leading to its exterior and having also assages connecting the chambers in the bloc with said exterior openings, an air compressor carried by the car, and a hose extending from each end of the air compressor cylinder to one ofthe exterior openings of the drill-block and a stud 'ortion of the pan and slidably connecting tfie piston-rod.

14. In a tunnel driving machine, the `combination with a car, of a drill-block pivotally mounted thereon vin front thereof, coacting means carried by the car and by the drillblock for oscillating it'about its pivotal axis, said block having a chamber formed in its lower portion, and, having also a passage 1434-112 extendingfrom each end of the chamber to theext'erior of the block, a piston andits rod mounted to reciprocate in said chamber, a an'pivotally hung near its rear end to and eneath the drill-block, the pan having near its front end a stud 'projecting through a hole in the piston-rod, an air compressor carried by the car, a flexible conduit connecting each end of the air compressor 4cylinder with one of the `passages. in the block, a horizontal conveyer carried by the car and adapted to receive material from the reciprocatory pan, a vertical conveyer adapted to receive material from the horizontal conveyer, and means for actuating the conveyers, the` relation of the reciprocatory pan and the horizontal conveyer being such that they are at all times during the oscillation ofthe drill-block'in proper position to transfer material from the pan to the conveyer. 15. In a tunnel driving machine, the lcombination with a drill-block having at its lower ortion a chamber and also a passage extending from each end thereof to the exterior of the block, a rolling support for the block, a piston and its rod in said chamber, a pan having a bottom formed with'upwardly and rearward-ly extending ribs, a pair ,of arms each nivotally connected to a si'de of the drill-block and'to a longitudinal side of the an near its rear end, a studxed'to the ont end of the pan and slidably engaging the piston-rod to permit the iront end of the pan during its reciprocation to rest on the ground, a bumper spring on the piston-rod adapted to stop with a jar the rearward motion ofthe pan, and means connected to said passages for supplying air under pressure to the iston chamber and adapted to alternate'ly establish unequal air pressures therein for re i rocatin the iston.

16. car, a f rill-b ook mounted u on the car, a pan havingtransverse ribs an a stud xed to its front end, arms ivotally suspending the an from the bloc i, a piston operative wit a chamber near its bottom and having the piston-rod connected to the stud of the pan, an air compressor and connections thereopwith said chamber for operating both the piston and the pan,v a buffer interposed between the stud and the block.

17. A drill block having a plurality of compressed air actuated reciprocatory drills, and having also a chamber in the lower portion of the block, a piston and its rod arranged to reciprocate in the chamber under the pressure of the compressed air, a pan pivot'ally sus ended from the block and beow the dril s and formed with transverse ridges, a'stud projecting from the pan and slidably engaging the iston-rod, a buffer adapted to eiect the su den stoppage of the rearward movement of the pan, and means for controlling the compressed air to actuate the drills, piston and pan.

18. In a tunnel driving machine, a block having a plurality of chambers, a thrusting drill in each chamber, the said block having passages leading from each chamber to external openings 1n said block, an air' compressor, a power actuated piston therein, a tube extending from one end of the cylinder of the air compressor to one of the block external openings, and a tube extending from the other end vof the cylinder of the air compressor to the other block external opening-the reciprocation of the iston of the Acompressor causing thereby the reciprocation of the drills, substantially as described,

19. A drill block, having a plurality of chambers therein, a drill holding chuck, and

a recinrocatory hammer in each chamber, said block having exterior openings and having also two passages leading from each chamber one of. the passages communicating with the chamber at the rear of its hammer and the other passage communicating with the chamber between the chuck-head and hammer and each passage connecting with one of the opposite exterior openings, and' means connected ,with the exterior openings and adapted to simultaneously produce unequal air pressures therein and cross channel'125-145 connectin adapted also to alternate these pressures in `the openings. y

20. A drill-block, having a plurality of chambers, therein, a drill holding chuck and a reciprocatory hammer in eadh chamber,

said block having inclosed major channels 86 88 formed in the block, and having also an opening connecting each channel with the exterior of the block, said block having a passa e extending from the rear of each cham erto a channel, and havin also a second passage extending from eac' chamber, between the chuck-head and hammer to the other channel the connection of the chambers to the channels alternating in the successive transverse groups of chambers, and meansconnected to the exterior openings of the drill-block for supplying air pressure thereto, the ressures su plied simultaneously to eacli -o ening lieing e ual, this means being also or the purpose o alternating in the openings and their connected spaces the une ual air pressures-therein.

21. A `drill-b ook, having a plurality of horizontal chambers therein and arranged in vertical series, a drill holding chuck and a reciprocatory hammer in each chamber, said block having inclosed major channels 86 and 88, vertically disposed in the block near its rear face, and having also an o ening connecting each major channel with the exterior of the block, said block having inclosed `minorvertical channels 79 and 81 inthe block near its front face, and having also aA each minor channel with the op ositely disposed major channel, said block havin connecting the rear ends of the c ambers of a transverse roup withtone of the major channels, and aving also a passage connecting the' front ends of the same chambers in front of the chuck-heads with the minor.`

channel connected to the last indicated major channel, said block having a passage connecting the same chambers at a point between the chuck-heads and hammers therein with the other major channel, and means connected tov the exterior openings of the drill-block for supplying air under pressure--the working pressure supplied to one exterior opening being greater' than that supplied to the other exterior oponing-this means being also for the'purpose oi' alternating the unequal pressures oi' the openings and their connected spaces for the purpose of actuating the hammers in transverse grou s which alternate in striking their chuc a blow.

22. A. drill-block, having a plnralit\v oll cham bers thereiina drill holding chuck and a reciprocatory hammer in each chamber, said block having inclosed channels 86 and 88 in the block, and having also an opening connecting each rhannel with the exterior of the block, said block having a passage extending a passage from each chamber between the chuck-head and hammer therein'to one of the channels, and having also a second passage extendlng from each chamber at its rear end to the' other channel the connection ofthe chambers to the channels alternating in the successive transverse groups of chambers an air compresser, a tube extending from each end o f the air compressor cylinder to one of theI ex? terior openingspf the block'fand means for supplymg the air-compressor, at each end of its cylinder with air under ressure the recip# rocation of the piston of tie air compressor causing the drills to operate in groups which alternate in striking a thrusting blow.

mer in eachv chamber, said section having inclosed major vertical channels 86 and 88 in the contiguous faces of the sections near one end' thereof, said sections having also in' closed minor vertical channels 79 and 81 in the contiguous faces of the sections near the opposite end thereof, said sections having passages 145-4125 connecting the minor vertical channels with the .oppositely disposed major vertical channels, said sections having so ,passages leading from the chambers at the rear of the hammer and connecting with one of the major channels, and'having also passages leading from the chambers 1n front of the chuck-head and connecting with the a 5 minor channel oppositely'disposed to the last indicated maior channel, said sections hav-v ing passages eading from the chambers between the chuck-head and hammer and connecting wlth the second maJor channel, said iasections having an opening 60-58 leading from each major channel to the exterior of 'the block, pipes one leading from each exterior opening to the cylinder of an air compressor the pipes being connected to opposite ends of the compressor cylinder which is thereby adapted to alternately establish unequal air pressures in the major channels and their connecting passages .for the purpose stated.

o 24. A drill block having a plurality of chambers formed therein, a reciprocatory drill holding chuck and a reciprocatory ham mer in each chamber, said block having major channels 86 and 8S in the. block near its rear face, and having also minor channels 79 and 8l in the block near its frontend, said block having connecting passages 145-125 between each minor channel and the o )positely disposed major channel, said b ock having a passage. extending from each chamber between the chuck and hammer therein to one ofthe major channels` said bl'oek having a second passage leading from the chaillbcrs at their rear ends to the other major c5, channel, said block having also a third passage-leading fromthe chambers at the front' ends in front of the chuck-head and'connecting with the minor channel that is connected to the last indicated major channel said block having an opening -58 connecting each major channel with the' exterior of the block, 4an air compressor a tube extending from each end of the cylinder ofthe air comressor to an exterior opening 60-58 in the lock,- and a flexible connection for a comlpressed air supply with the cylinder of the air compressor and adapted to maintain in the latter when it is not in operation e ual air pressures in the opposite ends of Aits cy in ders and-in the spacesin connection therewith for the purposeistated.

25. A drill-block formed of'a plurality'of rigidly connected longitudinal sections each section having a series of horizontal chambers', a drill holding chuck having a head. in each chamber, a hammer in each' chamber,

said block having inclosed major verticalchannels 86 and'88 in the contiguous faces of the sections near the rear thereof, said block v having also inclosed minor verticalv channels 7 9 and 81 at the contiguous faces -of the sections near thefront thereof, said block havof thechuck-headto the minor vertical channels, said block having also passages leading from the chambers between the chuck-heads and hammers, and connecting with the maj or vertical channels, the passages heilig so disposed that the transverse groups of chambers alternate in their connection with the major vertical channels and with the minor vertical channels, said block having an opening connecting each major vertical channel with the exterior of the bloclgan air compressor, a tube connecting cach end of the cylinder of the air compressor with an exterior i pening of the drill-block, said air compressor having a chamber 133 formed on the exterior of the air compressor cylinder, inwardly ol'iening valves connectingthis chamber with thesp'- posite ends of the cylinder of the air compressor and av compressed air supply connected with the chamber the reciprocation. of the piston of the air compressor resulting in the 'operation of the drills in transverse groups which alternate in striking a thrusting blow.

26. A drill-block, having a plurality of chambers therein, reci procatory drills in the chambers, said block having exterior openings forined in the drill-block, said block having also passages connecting the chambers with the exterior openings, an ai r compressorl a pipe leading from cach end ofv thel cjyin'- lic , opening of the block, an air compressor,

block, t

. porting diskin each opening the disk having end of the cylinder of the aircoinpressor to drill-holding chuck having an enlarged head -be reciprocated to strike the drill-carrying 'tube leading from eachend thereof to the end der thereof to one of the exterior openings, a tube leading from the compressed air supply to both ends of the cylinder of the air conipressor, valves adapted to cut oif either end ofthe air compressor cylinder from the coni pressed air supplypduring a stroke of the air t compressor piston which alternately compresses and expandsthe air-under pressure in the pipes leading from the ends of its cylinder this resulting in unequal pressures in the opposite ends of the dril chambers which causes the reci rocation of the drills.

27. A drill lock, having -a horizontally disposed chamber therein, a drillcarryin chuck and a reciprocatory hammer mounte in the chamber, said block having a passage leading from the rear .of the chamber at. the rear of the hammer t0 an exterior opening of the block, said block having a'lso a passage leading from the chambef between the chuck-head and hammer 'to the vexterior means for supplying compressed air to the cylinder of the air compressor at each side of its piston, and tubes one leading from each one of the exterior openings of the block.

2,8. A drill-block having ahorizontal chamber the front portion of which is of greater diameter than the rear portion thereof, a

adapted to be reciprocated in the'frcnt portion f the chamber, a hammer seated in the rear portion of the chamber and adapted to chuck, the' said chamber having the following connecting passages-one leading from its rear end and terminating at the exterior of the block, a second connecting the first passage with the front portion of the chamber in front of the chuck-head, and a third passage connecting said chamber between the rear of the chuck-head and the front end of the hammer and communicating with the exterior of the block independently of the exterior opening ofthe first passage, an air compressor, a

of each passage opening at the exterior of the e said air compressor having an exterioi; air chamberpinwardly opening valves connecting this air chamber with each end of' the air compressor, and a tube connecting a compressed air sup ly in communication with the air cham er, the valves being adapted to close when the air compressor piston approaches them.

29. The combination with a block and reciprocatory drills carried thereby, of a guide and guard fixed to the block in front thereof and consisting .of a face-plate having openings inalinem'ent withthe drills, a drill supanopening adapted to receive and support a drill the center of the opening inthe disk being in alinement with the longitudinal axis sei-,473

of the drill, and side plates projecting for,- wardly from the face-plate.

30. in a tunnel driving machine and in fcombination, a car, a pivotally mounted block at the front thereof, drills carried by saidbloek, means for operating the drills,

l and means ,whereby thecar is caused to advance in the cutting. operation, and means for guiding the car in its advance consisting of a pair of arms pivoted to each side thereof, the other end of each arm terminating in a roller, a screw-rod pivoted to eachV arm, aA sleeve for each screw-rod pivotally mounted on the car and adapted to slidingly support said screw-rod, and a nut engaging the screwrod, swiveled tothe sleeve and adapted toadjust the screw-rod toward or from the car. 31. In a-.tuniiel driving machine and in combination, a car, a pivotally mounted Ablock atvtlie front thereof, drills carried by said block, means for reciprocating the drills, a plate mounted on the block and having openings, and a collar-'for each drill xed in eachA opening and' forming a support and guide for the reciprocating movements of the drill. f y

32. In a tunnel driving machine and in combination, a car, a pivotally mounted blockl at the front thereof, drills carried by 'and projecting from the frontof said block, means for reciprocating the drills, and means secured to Asaid block for supporting and .guiding the projecting ends of the drills in their movements. l l v 33. Ina tunnel driving machine, a car having at its front end an arm at -its top and at its base projecting forward, a drill-block piv- 'oted to swing laterally on said arms,means` for automatically oscillatingthe drill-block upon its suspending pivot bearings, drills carried by the block the upper and theflowermost rows of drills respectively inclining upward and downward, reciprocatory hammers for actuating the drills, and fluid connections for actuating said hammers.

34. In a tunnel driving machine, and in combination, a car, a block pivoted to the car at the front thereof, drills carried by and projecting from the front of the block, means for reciprocating the drills, coacting means carried by the block and the car and adapted to swing the block automatically and con tinually in reverse directions about its pivotal axis the means carried by the block adapted tomake alternate contact with the means carried by the car.

35. In la tunnel driving machine and in. combination,v a car, a blockv ivotally mounted on-the front thereof, drill)s carried by andl rojecting from the front of the block, means or reciprocating the drills, a shaft from which power, for the oscillation of the block is derived and arranged in alinemeiit with the pivot mounting of said block, means actuated. by said shaft to automatically swing i it the drill-block in continuous reverse directions including vthe bevel gear 22 on said shaft, the clutch-gear 23-24 the worm-gear 25, the slidable rod 27 its pin 28, and the se mental rack having the arms 27-39' `l a apted ltomakealternate contact with the pin-128, and means for causing' the car to advance inthe cutting operation.

36. Ina tunnel drivmg machine, a car having an arm at the top and at the bottom projecting in front thereof, a drill-block pivotally mounted mediately of its width 'upon said arms, a pair of supporting rollers mounted at the base ,ofsaid block 1n advance of the pivot mounting thereof and arranged to ltrat'fel -in the `are of a circle described by thev oscillations of said drill-block, means for aul tomatically and continuously oscillating said drill-block and means for causing the car -to advance in the cutting operation.

3.7. 'In a tunnel driving machine and in combination, a car, a pivotally mounted 'block at the front of the car,`means for oscillating the block, drills carried by said block., an air compressor, ilexible conduits connecting the latter with the block for operating the drills during the swing movements of the block, and means whereby the car is caused to advance. s

3.8,. A .tunneldriving machine comprising in cooperative organization the following instrumentalities a car, a block, drills arranged in roups within said block, means for pivota ly mounting said block upon the car, means whereby the .drills areI actuated by compressed air in groups which alternate.

in striking a thrusting blow, means for horizontally oscillating the drill carrying block y as the car advances, means for limiting the front of the car, a pair of arms pivoted to each side of the car, a roller carried by each arm at its outer end, and means for adjusting'the roller ends of the arms toward and from the car consisting of a screw-rod pivoted vtofeach arm, a sleeve for each screw-rod pivotally mounted on the carand adapted to slidingly support the screw-rod, and a nut engaging the screw-rod and swiveled in the sleeve and adapted to adjust said screw-rod in the sleeve and ,to secure the rod in an adjusted position.

40. A car, a pair of arms, pivoted to each side, a roller carriedl by each' arm at yits outer end, a screw-threaded rod pivoted to each arm, a sleevefor each screw threaded rod the sleeve being pivotally mounted on the car and adapted to slidingly support the screwthreaded-rod, and a/nut engagingthe threaded rodI and swiveled to the sleevey and adapted to slide the threaded rod in the sleeve and to secure the rod in an adjusted position. y

41. Inl a tunnel drivinglrmachine, a car, a block, pivoted thereon, t usting drills car-v ried by the block, means for changingv the horizontal angle of the drill-block with reference to the line of travel off the car, and

adjusted to maintain the roller bearings in engagement with the sidesf' the tunnel for 'the lateraladjustment of tie carat either end and for guidance of the car and for holding it in position in the tunnel.

42. In'a tunnel driving machine, a'car, a block pivoted thereon, thrusting drills carried by theblock', means for changing the horizontal angle of the drill-block with reference to the line of travel of the car, and means adjustably mounted on each side of the car for its guidance and for holding itin position in the-tunnel and consisting of arms coupled together in pairs and pivotally secured at their meeting ends at each side of the car, the outer end of each arm having a roller, a screw-rod pivoted to eacharm near. its roller end and a universal joint connecting the screw-'rod to the side of the car.

43. In a tunneldriving machine, a car, a block pivotally mounted thereon, thrustingy drills carried by the block, a'muck-pan suspended from and'beneath theblock, .and

means connecting it to` the pan for causing it to have a reciprocating movement.

44. In a tunnel `driving machine, and in combination, a car, and means for advancing it against the breast of the tunnel, a drillhead carried in front of the car, and arms pivotally mounted at each side of the car extending therefrom obliquely to the front and to the rear, and each having roller bearings adapted to engage the side walls of the tunnel, "and means for adjusting said arms for the purpose stated.

In testimony whereof I have signed 'my name to this specification in the presenbe of two subscribing witnesses, March 4th, 1907.

GEORGE ALLEN FOWLER. 

